Performance improvement of green QW LEDs, for the different doping in the barriers, using InAlN interlayer and strain compensated AlGaN interlayer at the InGaN/GaN interface

Abstract

Abstract Significant improvement of green emission using different doping in the barriers has been studied when the In0.2Al0.8N interlayer (IL) or Al0.8Ga0.2N IL is used at the interface of In0.26Ga0.74N/GaN QW LEDs. With the increment of doping in the barriers the transition energy(TE) and the square of the overlap of electron and hole wave functions ( M e h 2 ) is significantly increased. We have considered the maximum barrier doping 1 × 1019 cm−3, beyond that, it may reduce the optical properties. It is seen that the maximum M e h 2 is obtained when the Al0.8Ga0.2N IL is used. Furthermore, we have compared the TE and M e h 2 with current, considering the ILs and without ILs. The best result is obtained when Al0.8Ga0.2N IL is used and it is more than 2 times higher than without ILs of LEDs at higher current. We have seen that the radiative recombination rate of QW LEDs with Al0.8Ga0.2N IL is more than 5 times higher than without ILs at the higher current. Due to significant improvement of the radiative recombination rate, the internal quantum efficiency of the devices has also increased significantly for different ILs. The J-V characteristics also shown, the diode cut-in voltage is increased when the ILs are used.